But there is need to do the laser projection or it works only with the infrared and cmos sensor? The laser isn’t just to know where are the keys?
Step 1: Template creation (Projection Module)
A template of the desired interface is projected onto the adjacent interface surface. The template is produced by illuminating a specially designed, highly efficient holographic optical element with a red diode laser. Note: the template serves only as a reference for the user and is not involved in the detection process. In a fixed environment, the template can just as easily be printed onto the interface surface.
Step 2: Reference plane illumination (Micro-illumination ModuleTM)
An infra-red plane of light is generated just above, and parallel to, the interface surface. This light is invisible to the user and hovers a few millimeters above the surface. When the user touches a key position on the interface surface light is reflected from this plane in the vicinity of the key and directed towards the sensor module.
Step 3: Map reflection coordinates (Sensor Module)
Reflected light from user interactions with the interface surface is passed through an infra-red filter and imaged on to a CMOS image sensor in the sensor module. Custom hardware embedded in the sensor chip (the Virtual Interface Processing CoreTM) then makes a real-time determination of the location of the reflected light. The processing core can track multiple reflection events simultaneously and can thus support both multiple keystrokes and overlapping cursor control inputs.
Step 4: Interpretation and communication (Sensor Module)
The micro-controller in the sensor module receives the positional information corresponding to the light flashes from the sensor processing core, interprets the events (e.g. keydown, keyup, mouse or touchpad control etc..) and communicates them through an appropriate interface to external devices.